Cars are equipped with an increasing number of electronic systems for various purposes; all these circuits need to be supplied from a primary voltage source to a lower secondary source. Power management is usually performed by an on-board power supply, but external sensors and modules must be wired throughout the vehicle and are exposed to harsh conditions. It must be ensured that the main power supply remains operational in the event of a failure in the off-board devices and that the ECU processor or other essential circuits continue to perform its task. Therefore, it is a popular measure to use so-called Voltage Trackers, where a reference voltage is replicated with high tracking accuracy and the safety level of the electronic system is generally increased.
This is what Ricoh has designed the R1540 for. The devices has a wide input voltage range up from 3.5 to 42 V, which makes it possible to use the voltage tracker in numerous cases. A regulator output voltage may vary due to electromagnetic noise interference (EMI), advanced technology is built-in to prevent such voltage variation. In addition the R1540 has superior immunity to EMI noise over a broad frequency band (150 kHz to1 GHz). Furthermore, it has a high ripple rejection ratio of 80 dB and a fast response to transients on input and load.
Some sensors require a highly accurate supply voltage to perform sensitive measurements; therefore, the voltage tracker provides a tracking precision of ± 15 mV.
What’s more, the R1540 has a series of safety features that protect the voltage tracker and other parts of the application from possible damage and defects.
More information: https://www.e-devices.ricoh.co.jp/en/products/power/vr_ldo/r1540/